The Heart to Your World
by Beeria
Summary: Princess Kairi is a mermaid, obsessed with the human world. When she saves the human Prince Sora from drowning the trouble begins. Based on Little Mermaid. Pairings: SoKai, Clorith. Maybe others later
1. Prologue

Disclaimer: Characters and places belong to SquareEnix and the basic story belongs to Hans Christian Anderson, though this is more following the Disney film so I suppose it's Disney's.

Okay, so this is my third Sora/Kairi fic, second movie for them. This will have similarities to the film but I'm going to change some things(even in this prologue you'll see at least one thing different XD) Also, I recommend that you have knowledge of KH and KH2 games as well as the Final Fantasy series, espeically 7 and 10 as there will be references later on in relation to these games and their characters.

Also, don't expect an update too soon. I'm busy battling the CloTis in the FF7 department at the moment lol but I'll try.

**

* * *

The Heart To Your World**

Prologue

The winds were calm and refreshing but it was still far too cold to stay out for too long without warm clothes on. The sea was also; thankfully, calm allowing the large ship to travel towards the deeper parts with no troubles and no worries about getting back. It was fishing season and it was vital to collect as much as possible since there was a threat of a famine this winter.

A young boy, not much older than sixteen was leaning over the edge of the starboard side, his deep blue eyes staring in awe at the waters below him. He had never seen it so clear before and it had never sparkled so beautifully under the rising sun either. He leaned over further, his crown pendent that he wore around his neck began leaning down but he did not care much about that right now. He just closed his eyes and let the breeze brush back his brunette locks.

"Sora!" the call of his name caught him off guard and he almost toppled right overboard.

Once he had straightened up, he threw a confident smile towards the owner of the voice, a silver-haired boy just a year older than he was. The boy named Sora brushed back his hair and leaned back against the woodwork, giving the other a raised eyebrow.

"You know if you fall in there you'll get abducted by the mermaids," he joked.

"Hey, Riku, stop filling his head with that garbage!" a raven-haired girl cried, putting her hands on her hips and glaring slightly.

"Everyone knows there are no such things as mermaids!"

"It was only a joke Yuffie," Riku muttered, rolling his eyes.

Sora just smiled and shook his head, gazing once more at the waves beneath him. The sea had always fascinated him. It had always captured his attention either when it was dormant like now or fierce in the middle of a storm. He often thought of all the creatures that existed down there. Dolphins, crabs, whales, starfish, clams…they all seemed so amazing to him even if it could have been seen as more of a girl thing to be in love with them, he was not ashamed to admit his feelings.

In reference to Riku's comment about mermaids, the young boy frowned. He had always wondered about those creatures that seemed to have an effect on almost everyone. Whether they were real or not, people knew what they were.

Sora, himself, was not sure as to whether to believe in them or not. He really did not care either way to be completely honest. After all, it was not as if they would ever affect him, with them being creatures of the deep after all.

"Hey, Sora, your chain is tangled up at the back," Yuffie said suddenly as she pulled the net up from the ocean.

The boy placed his hand to the back of his neck, annoyed to find that the girl was indeed correct and a knot was present in the back of his chain. It had probably happened when he had tossed it off carelessly before going swimming and not bothering to check it before throwing it back on.

He carefully lifted it up above his head and began trying to smooth the chains out but the moment he took it in his hands, the boat jerked and with a gasp, his beloved chain splashed into the water below him.

"No!" he cried in shock, causing Riku and Yuffie to glance at him. Little did he know that his precious pendent would fall into safe hands.

* * *

The red-haired girl let out a gasp as the chain fell into the water, watching it float slowly down into the water. Glancing up, she could make out his face looking shocked, upset and angry all at once. Once she was sure that his the pendant had fallen into the dark depths where he wouldn't see her, she flipped her purple finned tail and carefully grabbed it, her eyes widening in wonder as her fingers glided over the smooth surface.

"Kairi!" the girl turned at the sound of her name, smiling when she saw a brunette making her way towards her.

"Your dad is going crazy!" she greeted, narrowing her jade eyes. The redhead now named Kairi rolled her eyes tiredly.

"Aerith, when isn't he?" she joked, placing the chain around her neck. The brunette swam back at the sight before giving a sigh.

"You better hide that from him," she warned tenderly. Kairi nodded and led the way back to the palace.  
"So, was that all you wanted to tell me?" Kairi asked, turning to glide through the water on her back so that she could face the other. Aerith blushed and shook her head.

"I…have you seen Cloud anywhere?" she asked, glancing around her. Kairi smirked and gave a small shrug.

"Why? Because you fancy him?" she teased, deliberately yelling the 'fancy' part. Aerith blushed harder and slapped her hand over her friend's mouth, giving a glare. Kairi batted it away and laughed.

"No, I haven't seen him, which is strange. Normally he's doing his annoying older brother act," she replied, pulling a face as she turned around to face the upcoming palace.

Kairi was King Cid's daughter, his youngest child. Cloud was her older brother who was the complete opposite of her. He hardly spoke to anyone and was fiercely obedient, like a member of the army. Whatever Cid commanded, Cloud obeyed without question whereas Kairi did as she pleased, and drove her family around the bend because of it. She reckoned she had received it from her late mother.

She stopped before the palace doors and took off the pendant, stuffing it in her little red bag and swimming to one of the pillars. She felt her way up it until she came to the part with a loose brick. Carefully, she pulled it out and placed her bag inside before replacing the brick. She flashed Aerith a smile before waving her hand to get the other to follow.

They swam down the corridor, the throne room visible ahead of them. Kairi entered confidently, flashing a smile towards her brother and father who looked at her in anger.

"Where have you been?" her father demanded, rising a little from his throne. Cloud floated beside him, arms crossed over his chest. Kairi bit her lip nervously for a second before flashing a confident smile. Cloud narrowed his eyes, unimpressed while Cid sighed, placing his beloved trident in its holder. He rose from his throne, eyes never leaving his daughter's.

"Where have you been?" he asked, keeping his voice calm. Kairi gave a small shrug before she answered.

"Nowhere special," she replied.

"Remember it's the concert tonight," he continued and she nodded. He sighed and dismissed her. Aerith glanced after her for a second before she threw a smile at Cloud before following her. Cloud blinked after her, a little confused.

"Seriously Aers, if your eyes were any bigger back there I would think you were a fly!" Kairi teased. Aerith pulled a face but didn't reply, instead just following her friend.

"Where are we going?" she asked eventually, stopping for a second. Kairi threw a confident look over her shoulder along with a smile before she answered.

"You'll see!"

"Kairi!"

"You don't have to follow me you know?" the Princess called as she dived down to swim along the bottom of the ocean. Aerith gave an agitated sigh.

"Yes I do. If I left you with my sisters then you'll get in trouble!" she argued but Kairi merely laughed.

"When am I not in trouble?"

"You know what I mean!"

"Yeah, I do," the redhead sighed before she stopped, a large grin forming across her face and her eyes lighting up. Aerith glanced to where she was looking and gave a small groan. Another sunken ship lay on the ocean bed, it's treasures surrounding the rotten wood. Aerith was used to Kairi's fascination with human materials but that didn't mean she exactly supported it. Merpeople were brought up knowing the evils of the world on the surface.

"Selphie and Olette are inside," Kairi said suddenly, snapping Aerith from her thoughts. That was another reason the older mermaid was often spotted with them. She always had to look after her sisters. Cloud was sometimes there too, looking after Kairi.

The Princess slipped inside the broken window easily and Aerith followed close behind. Almost instantly, she was tackled by two younger brunettes, their playful giggles filling the air. Selphie had a yellow fin while Olette had orange. Other than that, the two were very similar in looks. While they were hugging their sister, they didn't notice Kairi swimming into the other room.

"Oh my gosh!"

"What is it?" the three brunettes cried, following the younger mermaid's voice. They stopped just behind her, staring ahead of them with wide eyes. Aerith put a hand on her chest. Kairi swam up to it, gently picking object up. It was a long key shape but other than that, she wouldn't have been able to tell anything about it.

"What is it?" Olette repeated, swimming around the Princess to get a better look. Kairi shrugged.

"I don't know," she sighed but smiled brightly. "But I bet Yuna, Paine and Rikku do!"

* * *


	2. Chapter 1

**Chapter One**

Selphie and Olette exchanged a high-five in excitement but Aerith looked less than happy about the idea of going to the surface. Kairi seemed to sense her gaze and gave her a slightly raised eyebrow in question.

"We shouldn't go to the surface," the brunette sighed. "It's dangerous and if your father found out then he would go mad!"

"Exactly," the Princess replied. "_If_ he finds out," she added, smirking slightly at Aerith's slightly annoyed expression. However, never one to take orders, Kairi simply glided past the older mermaid, throwing a cocky grin over her shoulder as she did so. Selphie and Olette followed their friend out of the shipwreck. They gave sympathetic smiles towards their sister as they passed. Knowing she had little choice, Aerith gave a sigh and followed them out. She knew if she let them go alone, they would end up in twice as much trouble.

Kairi seemed born without fear to Aerith as she watched the redhead break the surface without looking for human boats at all. The oldest brunette feared that one day her lack of awareness would be the death of her. However, luckily, there were no boats around and they were safe enough to go up to the surface.

Selphie and Olette were not as obsessed with the human world as Kairi was but they supported her through it anyway. They just didn't see what was so amazing about a bunch of legs. Perhaps, it was just another gene that they shared with Aerith.

The four mermaids waited at a rock for a moment, glancing around them every so often in search of any fishermen boats around. Kairi's eyes fell upon the beach when she heard voices and instantly, she pulled Selphie from view and signalled for the others to follow suit.

"I don't see what the big deal is Sora," a male voice sighed. "We can easily get you another pendant."

Aerith glanced at Kairi, who had turned bright red at the mention of the name "Sora." Catching her eye, the brunette raised an eyebrow in question but that only served in brightening the younger mermaid's blush and she turned her head away. Aerith smirked a little but refrained herself from teasing the redhead.

"Come on, let's go," she whispered to her sisters, smiling at Kairi's little nod in thanks. Aerith led the way to a small cave by the mountains at the edge of the beach, making sure all the mermaids were hidden from the view of the males on the beach. The cave was so small; the back was there almost as soon as you entered. As if suddenly realising where she was, Kairi snapped out of her daze and brought the large key to lean against her shoulder as she looked around her.

"Yuna? Rikku? Paine?" she called, glancing around her.

Instantly, three dots of light appeared and danced around above them, slowly and gracefully falling towards the rock that stood before the four mermaids. As they came closer, the colours of the lights became clearer. The one on the far right was dark blue, the middle was yellow, and the last one on the left was black.

The moment the lights touched the tip of the large rock, they took on human shapes and, with a burst of their respective lights, three young fairies were before them, grinning widely.

"Hey Kairi!" greeted the one on the right kindly. She was dressed in a strapless white top that tucked into her long blue skirt, which had a large slit on one side to reveal one of her thin legs. Her eyes were different colours, one green and one blue but they both held a sweet sparkle of welcome in them.

"Hello Yuna," the red-haired mermaid replied before looking to the blonde fairy beside Yuna. She was dressed in yellow shorts and a matching crop top and her wild hair was held together with random bits of red and blue ribbons.

"It's been a while. We've been bored stiff in this place while you go around chasing your sweetheart," she huffed mockingly. Kairi rolled her eyes.

"I do not chase him Rikku!" she replied. "I just…watch him from afar."

The last fairy snorted. "Same difference."

"Shut up Paine." Rikku retorted but her grin showed she was only joking around. "I think it's romantic. Tragic, with you being a mermaid and all, but it's romantic."

Aerith cleared her throat. "We came to show you something we found. Kairi was wondering if you knew what it was."

Immediately, Kairi handed the key over to the girls who gasped upon seeing it. Rikku tentatively held out her hand to stroke the smooth metal but just as her fingers would touch the handle, she jerked away. Yuna bit her lip in an expression between awe and worry. Paine was the first to recover.

"Where did you find this?" she breathed, her eyes fixed on the object. The mermaids exchanged worried glances with each other before Olette spoke.

"It was in an abandoned ship. Is it bad or something?"

Yuna shook her head. "No, it's not bad at all. In fact, it's really good news."

"Brilliant news!" Rikku added, punching the air. Kairi's eyes lit up as she swam to the edge of the rock and gripped it tightly.

"What is it?" she cried, desperate to know.

"This is a keyblade." Yuna said. "It is a weapon used against the heartless."

"Heartless?" Kairi repeated in puzzlement.

"The heartless are creatures that don't have hearts." Paine explained with an air of boredom about the whole topic. She had explained it many times before to other people so she was fed up now.

"They take the hearts of the living in order to try and become whole again."

A look of fear crossed all the mermaid's faces and the fairies seemed to notice. Rikku grinned reassuringly.

"Hey, don't worry though!" she said quickly. "There are no heartless in these parts, we check all the time."

"Besides," Yuna added. "If any heartless were to come along, you'd be perfectly safe with the keyblade."

"No." Paine cried suddenly, glaring at Yuna as if she had said something offensive towards her. "The keyblade already has a master and it's not Kairi."

The Princess glanced down at the key in her hand and frowned. "Well, how come I can hold it?" she asked.

"You can hold it but you can't use it." Paine replied. "If heartless do come along, your only hope is to keep holding on to your light. Don't let their darkness take you."

"And on that note," Rikku said suddenly. "We should get going. We have a performance in approximately an hour and we need to get ready. See ya around." The fairies waved cheerfully before they disappeared with another burst of light. Kairi's eyes widened.

"The concert!" she wailed. "Daddy is going to kill me!"

She quickly dived underwater, her friends close behind. She willed her fins to move as fast as they could go, which was hard with the large and heavy keyblade to drag with her. Sensing her struggles, Aerith grabbed the other end of the blade and the mermaids swam together in a straight line with Olette on Kairi's left and Selphie on Aerith's right.

"Kairi! You can't go into the palace with that!" Selphie scolded, coming to a stop. Aerith and Olette followed suit and Kairi let out an agitated sigh.

"You're right," she agreed. "I hope he's in a good mood," she added with a mutter.

The mermaids did a quick u-turn and headed down a thin gorge and through one of the underwater gardens. Aerith was often found in one of them, picking some pretty flowers for everyone but today she had to restrain the urge to do so and concentrate on helping Kairi to her secret cove where she kept all the things she had found from the human world.

Selphie and Olette swam to the large rock that guarded the entrance and Selphie pushed from the left while the other brunette pulled from the right. Kairi and Aerith quickly swam through the opening. Selphie and Olette dived through the gap just before the rock slammed back into place. Aerith let go of the keyblade and watched as the Princess scanned the hideout for a suitable place to put it.

Finally, after a few moments, Kairi swam to the centre of the cove and placed the key on the rock that stood proudly. She tilted her head to the side, as if still contemplating that it really suited that position but Aerith soon distracted her.

"We've got to go Kairi. Your father will be throwing a fit!"

Kairi nodded and followed the older mermaid out. Selphie and Olette let go of the boulder, allowing it to hide the entrance once more. The four swam towards the palace doors, the guards letting them past without a second glance. The three brunettes hovered in the background as Kairi entered the throne room to meet her father and Cloud.

"Where have you been?" Cid demanded, narrowing his eyes dangerously. Kairi upturned her palms and gave her most innocent smile.

"Here and there," she replied. "I was with Aerith, Selphie and Olette."

Her father glanced towards the doorway where he could see the three young mermaids waiting for Kairi. With a sigh, he slowly shook his head.

"I don't know what I'm going to do with you. Go and get ready for the concert," he muttered, waving his hand dismissively. Kairi flashed a grin at her father before sticking her tongue out at Cloud's disapproving expression. It wasn't until she approached her friends that her grin faded and a sudden realisation flooded her.

She hadn't rehearsed a song!

* * *


	3. Chapter 2

**Chapter Two**

"Okay Kairi, calm down!" Aerith said, grabbing the younger mermaid's shoulders gently. Kairi took a couple of deep breathes and nodded.

"You're right," she muttered. "You're right Aerith. I've got to calm down."

"It's got to be here somewhere," Selphie piped, swimming over to the shells in the corner of Kairi's room. Olette nodded and swam over to Kairi's bed, checking underneath.

"Kairi, what's taking so long?"

The mermaids froze as Cloud's voice drifted towards them. The redhead suddenly pulled Aerith's hands off her shoulders and shoved the brunette outside the room. Aerith turned with a bewildered look on her face.

"Distract him!" Kairi hissed. The older mermaid opened her mouth to protest but the princess had already pushed the boulder over her doorway, preventing entry.

"Aerith, where's Kairi?" Aerith turned to face him and smiled innocently.

"She's just getting ready," she assured him, pressing herself against the boulder in an attempt to keep him away. He studied her carefully.

"She's been getting ready for over an hour. Let me in."

"No, she's nearly ready okay? Give her five more minutes!"

The blonde stared at her for a few seconds before he looked away. "Fine but not a second longer!" he said before swimming away. Kairi pulled the boulder back and gave Aerith a wide grin.

"I'm going to kill you!" Aerith screamed. Kairi laughed.

"Got you talking though didn't it?" she teased as she turned to her mirror. Aerith looked as though she was torn between thanking the redhead or strangling her. Selphie thankfully saved her the trouble by finding Kairi's song sheet and handing it to the Princess. She glanced briefly at the lyrics and pulled a face letting out a short sigh of annoyance.

"I hate that song," she muttered mostly to herself. "I'm going to do another one."

"You don't have time to learn another one!" Aerith replied.

"I'll make it up," the redhead answered with a shrug. Aerith looked set to reply until Cloud entered the room with a look of annoyance on his face.

"Get out there now!" he hissed. Selphie and Olette swam out of the room without wasting a second. Kairi remained where she was, sorting her hair in a deliberately slow manner. It was only then that Cloud seemed to realise the mirror and other 'human' things littering her bedroom. For a moment, he looked as though he had lost his voice before he turned to face her again.

"Where did you get all this Kai?" She shrugged and gave him her most innocent look.

"Nowhere special," she said. Cloud glared.

"You've been to the surface haven't you?" he stated, his voice cold. The redhead bit her lip.

"Only for a moment!" she answered. "Nothing happened!"

"Kairi! Are you insane? They could have killed you! Dad has that law for a reason!"

"You don't know any humans! Dad doesn't know the humans! Some of them could be nice!" she snapped.

"Nice?" her brother repeated. "Don't make me laugh! I wonder if you'll think they're nice after they snare you in one of their nets!"

"Oh shut up Cloud! You're always so arrogant and trying to be perfect all the time!" she snapped before she shoved him out of the way and swam out of the doorway before anyone could respond. Aerith blinked before she quickly followed her friend down the corridor.

"Kairi, what about the show?" Cloud yelled.

"You can tell Dad I'm not interested!" she called back without looking at him.

"Dad's going to kill you!"

Kairi pretended she did not hear him and swam faster. Aerith said nothing, taking note of Kairi's furious expression. She followed silently as they made their way to her secret trove where she sat on one of the rocks sadly.

"Why can't he leave me alone?" she sighed. "Not all humans are that bad."

"Like Sora?" Aerith asked teasingly.

"Like Sora," Kairi repeated with a goofy smile on her face. Aerith shook her head.

"You don't know him," she pointed out. "You've never spoken to him and you've only seen him from afar."

"He's not like the humans Dad tells us about though," Kairi pressed. "I know he's different! Besides, it's not much different from you and Cloud."

"What?"

"You never speak to Cloud but you're in love with him right?"

Aerith opened her mouth to speak when a shadow fell across them all. Kairi looked up at one of the small openings in the roof of the cave. A look of excitement crossed her face as she saw a ship across the surface. Without a word, she took off, swimming upwards to the surface.

"Kai? Where are you going?" Aerith called, following the younger mermaid.

"It's his ship!" Kairi squealed before her head broke the surface. She pushed the hair out of her eyes and gazed at the large boat in wonder and awe. Aerith appeared beside her a moment later, glancing around in panic.

"Kairi, we shouldn't be up here! We could be…" she began but she wasn't given the chance to finish as Kairi had already began swimming towards the side of the ship and lifting herself up onto the platforms on the side. She pressed herself close to the wall and slowly peeked around. Sora was there, sitting on the deck by the port side with a sad look on his face. She felt her breath catch in her throat as she watched him. From this close up, he was even more beautiful.

"Kairi!" Aerith hissed, snapping her from her daze. The redhead had almost forgotten that Aerith was there. Frowning, she put a finger to her lips and looked back towards the scene. Kairi was so absorbed in watching him she didn't noticed Rikku, Paine and Yuna approach until Rikku pulled playfully on her hair. Kairi waved her hand dismissively and focussed back on the scene.

"What are you doing out here?" Rikku asked.

"Shh!" Kairi hissed, pointing towards Sora as a warning. The three girls giggled.

"Kairi and…" Rikku began to sing but stopped. "Wait…what is his name?"

"Shut up!" Kairi muttered as she looked back at Sora.

"Don't worry Sora, we'll get you another pendant!" a woman assured him. He attempted a smile, which wasn't very convincing.

"It's not the same Yuffie," he sighed.

"Think of it as a birthday present," she insisted. "Any pendant you want! Well, except my Materia one but any other!"

"Could have been a wedding present," an older brunette muttered.

"Aw Leon you're not going to start that again are you?" Sora wailed, letting his head rest against the ship. The ship was silent for a few seconds as everyone felt the tension rise.

"Everyone's waiting on you to marry Sora!" Leon continued.

"I'm not ready to marry yet," he protested. "I'm only sixteen!"

"That's old enough to marry," Leon replied.

"Yeah but it's also the right girl!" Sora answered. "If I have to marry, I want it to be with the right girl. Not just because of benefits for the Kingdom but for me."

"Have you any ideas about this right girl of yours?" Yuffie asked with a smirk.

"I'll know when I see her," Sora answered. Kairi listened carefully a feeling of sadness overwhelming her. She wanted to be that right girl but it wasn't possible, not with her being a mermaid and him a human. "It'll just hit me, like lightning."

Almost as soon as the word escaped his mouth, thunder echoed around them. Sora looked up to the sky in surprise as a flash of lightning appeared only to be followed by more thunder. Kairi grabbed the rigging, as the winds grew more frantic. She faintly heard Aerith scream and saw her diving under the water. Rikku, Paine and Yuna were caught on the high gale, their little wings unable to get them out. The ship tilted dangerously to the side, throwing most of the crew into the water. Kairi's hands slipped and she fell into the water.

Instantly, she turned to face upright and broke the surface once more. She attempted to move against the waves, her eyes searching the area wildly. She could see most of Sora's friends and crew getting into a boat but there was no Sora. She turned to face the ship again as lightning flashed again, catching the rigging.

"Sora! Jump!" Leon yelled from the small lifeboat. Kairi looked back up at the deck and could make the brunette out.

"I can't swim!" he called, his voice full of panic.

"We'll catch you!" Yuffie promised, holding out her arms.

The rigging toppled from the weight of the flames, forcing Sora to jump back in order to avoid being squashed. The mermaid forced herself closer while making sure to stay out of the vision of the others. Sora took a step back, colliding with the steering wheel as the flames began to inch closer. He looked between them and the water before he closed his eyes and jumped.

Kairi's eyes widened as she watched him jump from the other side of the ship. The waves became more frenzied, sending the boat with Sora's friends further away from the place where their ship was slowly descending into the sea. Kairi dived underwater, swimming under the ship wreckage in order to get to him.

She saw him further ahead, slowly sinking further underwater. His movements were tired and she could see his eyes beginning to fall closed. Without thinking twice, she reached for him, her arms circling his waist and pulled him back to the surface. He took a long breath, glanced at her for a moment before he collapsed, his body exhausted from the effort it had just gone through. Kairi tightened her grip and pushed against the waves as the shore came into her view.

* * *


End file.
